Aquarium filter cartridge



FIG. 1 is a front elevational view of an aquarium filter cartridge showing our new design;

FIG. 2 is a side elevational view thereof, the opposite side being a mirror image,

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof. 

The ornamental design for an aquarium filter cartridge, as shown and described. 